Fractionated Stereotactic Radiation Therapy for Pituitary Adenomas: An alternative escalating protocol of hypofractionated stereotactic radiotherapy delivering 35Gy in 5 fractions

Cancer Radiother. 2022 Jun;26(4):557-562. doi: 10.1016/j.canrad.2021.08.021. Epub 2021 Oct 26.

Abstract

Purpose: Evaluate efficacy and toxicity of hypofractionated stereotactic radiotherapy (HSRT) for patients treated for pituitary adenoma (PA) with an alternative HSRT escalating protocol delivering 35Gy in 5 fractions.

Material and methods: From June 2007 to March 2017, 29 patients with pituitary adenoma were treated in Antoine Lacassagne Cancer Centre with an alternative HSRT protocol. Prescribed dose was 35Gy in 5 fractions of 7Gy. Radiographic responses were assessed by annual MRI. Hormone blood samples were evaluated each year after HSRT.

Results: A total of 29 patients aged between 23 and 86 years (median 54 years) were included. Twelve patients received HSRT for recurrent cases and 12 received postoperative adjuvant HSRT, 5 patients did not have surgery. After a median follow-up period of 47 months local control rate was 96%. One patient presented an out-field tumor regrowth 73 months after HSRT. The majority of PA were endocrine-active (18 patients, 62%). After HSRT, 8 patients (44%) presented complete response on initial secretion, 4 patients (23%) presented partial response on initial secretion. Four patients (14%) presented grade 2 or more acute radiation toxicities. One grade 4 visual disorder was observed for one patient.

Conclusions: HSRT delivering 35Gy in 5 fractions represents a feasible treatment and shows promising results to reduce hormonal overproduction and to improve local control in PA.

Keywords: Adénome hypophysaire; Endocrine-active; Escalade de dose; Escalating dose; Pituitary adenoma; Radiothérapie stéréotaxique; Stereotactic radiotherapy; Sécrétant.

MeSH terms

  • Adenoma* / diagnostic imaging
  • Adenoma* / radiotherapy
  • Adenoma* / surgery
  • Adult
  • Aged
  • Aged, 80 and over
  • Brain Neoplasms* / radiotherapy
  • Humans
  • Middle Aged
  • Pituitary Neoplasms* / diagnostic imaging
  • Pituitary Neoplasms* / radiotherapy
  • Pituitary Neoplasms* / surgery
  • Radiation Dose Hypofractionation
  • Radiosurgery* / methods
  • Retrospective Studies
  • Treatment Outcome
  • Young Adult